wzard999

The easy way.

Feel free to skip my babbling. Instructions are in blue.

Hey folks. I nailed a great deal on a USDM OEM fog light kit for the xA about a month back. Got them all properly wired up and installed according to the included instructions. But there was one pretty major aspect of the lights that bugged the heck out of me. That is, they would only function with the headlights turned on. I couldn't help but ask myself, "So, what's the point of having fog lights if they don't properly function in foggy/snowy/rainy conditions?"

Illuminating the precipitation with the headlights while the fog lights are turned on entirely defeats the primary purpose of fog lights (i.e., to illuminate the road instead of the precipitation). I had to have fog lights that worked with the headlights turned off. Simple as that.

So, I dug up a bunch of DIY tutorials here at scionlife and over at the xb site, but all of them were overly complicated and different from one another. To say that I was confused by the multitudes of different ways to go about this would be an understatement. Some methods worked with the parking lights; some methods worked without; some methods worked with the brights; some methods worked without; some methods required accessory power; some didn't; some methods required only battery power; some didn't; so on and so forth. . .

Finally, to save myself the frustration of milling through so many different methods, I went straight to the source and dug up an electrical manual for the 2005-06 Scion xA. The diagram attached to this post was my primary assistant. Here's the link for those interested in downloading the entire manual. It's pretty awesome: http://library.worldtracker.org/Car%...iagram/EWD.pdf

Looking at the diagram, it is evident that the yellow wire (from negative pole of relay to fog switch) and the red/light-blue wire (from fog switch to combination switch [i.e., headlight switch]) lead directly to ground. So, in order to give the fogs independent functionality, all I had to do was eliminate the fog switch's reliance on the combination switch's ground. Easy enough. Why resort to all the complicated methodology of other tutorials when all I had to do was ground the red/light-blue wire that is exiting the fog switch? The kicker is that the fogs - when the red/light-blue wire is directly grounded to chassis/body - will remain on when the ignition is turned completely off because the fogs are powered straight from the battery (as also evidenced within the uppermost part of the attached diagram). As a result, by going this method, I would need to remember to switch off the fogs after shutting down the ignition. That's it. That's the only downside. Fine by me because the work involved is comparatively much simpler than any other method I could dig up.

Using the method I describe here, the fogs would remain on when the headlights were turned off. The fogs would remain on when only the parking lights are turned on. The fogs would remain on when the brights were turned on. Essentially, just by grounding that red/light-blue wire, the fogs would remain on whenever switched on through the fog switch.

The work:

Pull the fog light fuse (under dash fuse box). Pull the fog light switch out of the dash. It's anchored in by a couple of snap/clips that can be pressed from the back side. Unwrap some of the tape, leaving plenty of wire exposed. Cut the red/light-blue wire behind the fog light switch leaving as much lead as possible to work with. In my case, I was able to leave about 4-inches of wire leading out of the switch. Solder or crimp an additional 3 feet of 20-18 AWG wire to this red/light-blue wire/ground lead (exiting the switch). Crimp an anchor to the opposite end of the new wire extension. Be sure to insulate these new connections with shrink wrap and/or electrical tape. Tape off the other, open end of the red/light-blue wire that you just cut. Don't ever leave any open wiring. Then, feed the new and extended wire/ground lead down through the back side of the steering column and down to the vicinity of the left, driver-side kick panel. Behind this kick panel is a ground bolt. Can't miss it. It has about a half-dozen white/black ground wires anchored to it. Anchor the new switch ground wire to this bolt. Replace the kick panel and rocker panel. Replace the switch to its position within the dash. Replace the fog light fuse. Replace the under dash fuse panel. And you're good to go. It's as easy as that.

Just be sure to switch off the fogs when you're finished using them. Should you leave the fogs switched on - contrary to the courtesy functionality of the headlights and parking lamps - there are no courtesy warnings indicating that the fogs are remaining on after switching off the ignition. I'm sure it could be wired for courtesy warning, but that would have been more pain than what it's worth. Not sure about you folks, but I've never in my life forgotten to switch off my lights when shutting down the ignition - even without courtesy buzzers and dash indicator lamps.

I hope this is easy enough. Much easier if you ask me than splicing into some other wiring, tapping fuses, pulling relays and what-not. Just ground that red/light blue wire. I'm assuming that the procedure and the wiring colors would be similar if not identical for a first gen xB. See the attached image for more electrical detail. And if you're interested in how the entirety of the electrical system works, take a look at that link that I posted above. With enough studying, you may be able to wire up this method with a courtesy buzzer. Have fun!

EDIT: My apologies. For some reason, the image that I uploaded was downscaled to a barely perceptible size. Please, refer to the diagram within the link. It's on page 152.